Optimum Earthquake Design of Shear Buildings

An approach for the automated optimum design of shear buildings against strong earthquakes is presented. It shows that the distribution of stiffness with height plays an important role in the member proportioning, being directly related to the story shear forces for response and the total weight of the structure. The importance of the stiffness distribution of multistory buildings on their dynamic response is illustrated through a parametric study. An approach is presented to seek the optimum distribution automatically using mathematical optimization technique. Multistory buildings without lateral bracing can be represented as a shear building which consists of lumped masses and springs. The standard response spectra recommended by Umemura are considered as external disturbance. A nonlinear programming technique, the sequential application of linear programming, is successfully applied to obtain the optimum design of several examples under constraint conditions for member stresses and story deflections.